In the transportation and storage of particulate materials, such as plastic beads for use in the plastic industry, it is common practice to use a drum made of fiberboard. Such containers are not collapsible; therefore, even though they are quite expensive, it is common practice not to ship them back to the point of origin. The cost of such one-way, non-reusable container is reflected in the cost of the product being shipped. Attempts to develop a container formed of a less expensive material, such as corrugated board, and one which is also collapsible for return shipment, have been less than successful. This is because the prior art constructions have been incapable of retaining powdered and particulate materials without leakage. The non-collapsible barrel is an added problem at the factory where the particulate material is produced, because of the fact that the container takes up so much space while in storage waiting to be used. In addition, the fiberboard container is quite heavy in proportion to its volume and this extra weight represents a shipping cost which is usually passed onto the consignee, whether or not the shipping cost is designated on his invoice as such. These and other difficulties experienced with the prior art devices have been obviated in a novel manner by the present invention.
It is, therefore, an outstanding object of the invention to provide a container which is collapsible and which is capable of containing particulate material without leakage.
Another object of this invention is the provision of a container formed of a single piece of corrugated board having a high strength, leak-proof bottom structure.
A further object of the present invention is the provision of a container which is light in weight and which, nevertheless, is capable of carrying high-density powders and particulate materials without leakage.
It is another object of the instant invention to provide a container formed of corrugated board which can be collapsed into a flat condition for storage and shipment.
A still further object of the invention is the provision of a container formed of a single piece of corrugated board having a high-strength, anti-leak bottom structure.
It is a further object of the invention to provide a container formed of a single piece of corrugated board having a closure structure with an integral pouring spout.
It is still a further object of the present invention to provide a container bottom structure including a panel which is supported beneath by straps and tabs all of which lie in substantially the same plane and occupies essentially the entire area under the panel, so that the panel cannot be distorted by fungible contents.
With these and other objects in view, as will be apparent to those skilled in the art, the invention resides in the combination of parts set forth in the specification and covered by the claims appended hereto.